Don't know if your aware, but I have a friend who works for ZF here in Nottingham. I have asked him about the gearbox in my 08 330d he said its not sealed for life! It has a service interval or 60-80k, bmw have apparently made it service for life in there wisdom. Might help someone knowing that, if you already knew then I shall shut up!

Remove 'box sump pan, drain oil as far as practicable (measure how much oil is removed) and then refill with fresh. You'll never be able to drain the torque convertor anyway so a full change will never be possible.

I honestly don't know what ZF can do, I only know a friend who works for them. I can ask if they can test a gearbox for you? But I don't know if it will be a test on a bench or a strip and check it out.

I honestly don't know what ZF can do, I only know a friend who works for them. I can ask if they can test a gearbox for you? But I don't know if it will be a test on a bench or a strip and check it out.

I think I got in touch with someone from nottingham when I was having troubles and they refused to deal with me because they dealt with the commercial stuff .. lorries and such like .. but I could be wrong , I called a lot of places !

All i'm interested in is the box to go on a rig to run it up and see if oil pressures are ok and gears change. Obviously something like that wouldn't come free but would be cheaper than stripping it down which for me would be prohibitively expensive.

I did have trouble with this box but am not 100% convinced that the box is goosed, I think there was an electrical issue elsewhere that caused funny bumps and thuds to happen.

If you could tap your contact up and see what he has to say , i'd appreciated it

A BMW Service Manager also told me that the gearbox oil can and probably should be changed but only if the car is expected to go on for 1,000,000s of miles.

I also read that the method that BMW use to change the oil and the method that gearbox specialists use differs in that BMW don't completely flush through the new oil but simply drain and top up. (Something like that!) Also remember seeing a figure of 11 litres, I think this was the figure needed for a complete flush through?

This is an old one - Merc said their autos were sealed for life and yet any number of V8 mercs (things like C43 and E55 from the late 90s) had gearbox troubles from 100k to 130k miles typically.
The cynics changed their ATF every 50k miles and never had any problems.

Needless to say i will be changing the ATF in my 'box at the next service (only just bought the car and it's on 62k miles).

A BMW Service Manager also told me that the gearbox oil can and probably should be changed but only if the car is expected to go on for 1,000,000s of miles.

I also read that the method that BMW use to change the oil and the method that gearbox specialists use differs in that BMW don't completely flush through the new oil but simply drain and top up. (Something like that!) Also remember seeing a figure of 11 litres, I think this was the figure needed for a complete flush through?

I to have been told by BMW that a oil change was all that was required and not a full filter change.

MY 330i will be going in for a change in March ish as at the back of the box there is a plug which is leaking (a small amount of) oil and this is apparently quite a common but can only be fixed with the filter removed.

I to have been told by BMW that a oil change was all that was required and not a full filter change.

MY 330i will be going in for a change in March ish as at the back of the box there is a plug which is leaking (a small amount of) oil and this is apparently quite a common but can only be fixed with the filter removed.

The filter is part of the sump, which is plastic and tends to warp with the heat and eventually leak. It is recommended to change the sump at the same time as the oil change.

PS: BMW also tell you that you never need to change the oil on this 'box and that it is a lifetime unit. I would question what BMW tell you...

BMW lifetime cycle for these gearboxes is wowfully IMO wide if the mark, we do shed loads of sump/fluid changes on E90's E60's incluiding Seb(ESS's) and other when inspceted the sumps are leaking as are the mechatronic sleeves.

Its not unusal to lose a good litre plus of fluid say over 5-6 years 80k(ZF recommend every 50k that the fluids changed and also with these cars ideally due to the way they leak the sump/filter combo) Mercedes and VW/Audi as manufacturers do a better job re ensuring their transmissions stay together by recommending fluid changes every 40k or so, which a lot of their customers actually do understand.

Quite why BMW went the sealed for life route remains a mystery, but put it this way if it was sealed for life then you'd expect difficulties in getting fluid/sump filter units yet call BMW for say a sump in the morning you'll have it in the afternoon and most dealers have fluid on tap or again can get it same day, so if its sealed for life why the hell would this stuff dealer wise be so accessable!

Stange. But moving on as an indy dealer we recommend every 50k or so miles the units changed, which is in line with ZF, when we service cars we always inspect and usually we find & report any leakage. Customers for instance sometimes report coming to a halt and expieriencing a thump from the transmission or delay's or abruptness re gear changes, usually this is all we need to look and usually we discover leakage.

When drained the fluid looks like this

dark, smelly and corupted by heat and other matters which means clearly the fluids not working as efficiently as it should hence the issues customers face. If you look at how shiny the sump is below

this is sweeting fluid that coated the underside of this particular sump(the sleeve was also coated in leaking oil-which is very common) So how can this last a life time

This is how the sump should look in place

Clean withno oil trace whatsoever.

Once the fluids changed
its recommended that the cars adaptations are re set for gearbox(via diagnostic)but as I've also discovered the other day re set the engine adaptations as well as this makes when combined a hige diffference as trhe engine ECU's taking to the gearbox ECU, both of which have become acustomed to the car driving with dirty leaking fluid over time. Re set these and the car with new fluid will adjust to its new fluid and trust me it really works.

A BMW Service Manager also told me that the gearbox oil can and probably should be changed but only if the car is expected to go on for 1,000,000s of miles.

I also read that the method that BMW use to change the oil and the method that gearbox specialists use differs in that BMW don't completely flush through the new oil but simply drain and top up. (Something like that!) Also remember seeing a figure of 11 litres, I think this was the figure needed for a complete flush through?

The BMW service manager needs his bumps feeling IMO. You can drain drop the sump nad change the fluid as stated in my previous poist above.

He's right re the quantity of fluid, you won't be able to drain the torque converter, you'll drain from the gearbox around 6.5 litres(providing it doesn't leak-when we drain its not unusual to drain barely 5 litres worst one we've had barely contained 3.6 litres of fluid) You won't get all the fluid out from memory its around 11.8 litres inc. Torque Converter but when changing the sump and re filling you'll get around 6.5 litres back in.

You can if you really want to stand a change of getting the best out of the change re visit the sump drain and re fill again after around 500 miles of motoring that way you might get a bit more of the older fluid in the conveter mixed up and drained, but its not really guaranteed that this method would be 100% sucessful, better do the sump nad fluid change run for say 4050k then repeat the exercise